God cannot be seen as He is unless He allows Himself to be seen, which is termed the beatific vision. This is an unapproachable light (1 Tim 6:16), but we expect to see face to face in Heaven (1 Cor 13:12, Ps 17:15).
The Catechism also tells us that we will reign in heaven, though obviously not over God, and this implies that Heaven is not a static place. Rev 22, even taken literally, tells us that Heaven will be an immense place, a place that cannot be on Earth as it is, and Rev 21 tells us that it will be a new place with no more sadness. Paul, in Rom 8, tells us that we are groaning to be part of this new creation. Jesus tells us that we must lay up treasure in Heaven. We also know that there will be gender in Heaven, as we are repeatedly told that there will be people of both specific sexes there.